Replaceable filter elements and assemblies including such filter cartridges have proven to be useful components of filtration systems for applications in internal combustion engines such as diesel engines. Replaceable filter cartridges can be provided along with other components of filtration systems to provide assemblies operable to filter liquids such as fuel, oil and other lubricants, hydraulics, and others.
In many fuel filtration systems, a filter cartridge is positioned within a housing or shell, with the shell then mating with other portions of the fuel filtration system. A lower endplate of the filer cartridge includes a gasket which forms a seal with an inner surface of the shell, thereby separating filtered (clean) fuel from unfiltered (dirty) fuel during operation of the engine system. Over time, the gasket has a tendency to swell or expand, resulting in an overcompression between the filter cartridge and the shell As a result, when it is time to replace the filter cartridge, it can be difficult to physically separate the filter cartridge from the shell. In this situation, a tool typically must be used in order to physically separate the filter cartridge from the shell.
FIG. 1 is a perspective view of a portion of a conventional fuel filtration assembly, showing the process by which a conventional filter cartridge 100 is removed from a filter shell 110 of the fuel filtration assembly via the use of a tool. As shown in FIG. 1, individual projections 120 extending from an endplate 130 of the filter cartridge 100 mate with recesses 140 formed in an upper surface of the filter shell 110. The close tolerance between each projection 120 and the corresponding recess 140, in combination with the tight seal between the other endplate's gasket and the shell's inner surface, results in a situation where someone wishing to replace the filter cartridge 100 must use a tool 150 (such as a screwdriver) to pry the projections 120 from the corresponding recesses 140. However, this technique of using a tool 150 can be problematic; the use of a tool may damage the shell 100 in certain situations. More particularly, the tool 150 could damage the recesses 140 in the shell, making it difficult to install a new filter cartridge 100. The tool 150 could also generate debris, which may go into the shell 110 and increase the possibility of “dirty zones” appearing in the shell 110. Still further the use of the tool 150 may result in personal injury due to misuse and/or accidents. Finally, in situations where there is little clearance space, there may be so little space to even use the tool 110 for the removal of the filter cartridge 105.